The main role of bacteria and fungi in soil is to decompose dead organic matter, which then forms soil. However, not all fungi are beneficial. Under certain conditions, bacteria and fungi can also be harmful by causing disease. The aim of this study is to explore soil bacteria and fungi and determine the diversity of bacteria and fungi found in oil palm plantations on the ITSI Medan campus. Soil samples were taken using a proportional random sampling method on an area of ????6.7 Ha. There are 2 soil sample points in every 7 trees taken inside and outside the disc. Microorganisms were identified in the Soil Biology Laboratory, Agrotechnology Study Program, Faculty of Agriculture, University of North Sumatra. There are several types of microorganisms obtained, namely from the genus Bacillus, Aeromonas, Micrococcus, Mycobacterium, and Enterobacter with a total of 7.183 x 106.

Background and aims: Healthcare associated infections are a major concern, causing an estimated 72,000 deaths and costing the United States up to $45 billion annually. This study aimed to identify and characterize bacterial isolates in healthcare facilities to improve infection control. Methods: Using biochemical identification and Pareto analysis, samples were examined to determine the most prevalent bacterial species. The Pareto principle helped focus efforts on the major contaminants. Results: Results showed that Pseudomonas genus (34.6%) and Micrococcus genus (19.2%) were the most abundant, accounting for more than 50% of isolates. The presence of multiple bacterial species, including both Gram-positive and Gram-negative bacteria, suggests widespread prevalence, likely a result of inadequate cleaning and contamination of water or surfaces. Gram-positive bacilli were less common due to their lower environmental resistance. Conclusions: The study concluded that implementing proper cleaning and disinfection protocols and regularly monitoring water quality are essential for preventing cross-infection and ensuring a safe environment. Identifying the most prevalent bacteria using the Pareto principle is a crucial step in mitigating the risk of microbial contamination. Peer Review History: Received 8 August 2025; Reviewed 11 September 2025; Accepted 19 October; Available online 15 November 2025 Academic Editor: Dr. Emmanuel O. Olorunsola, Department of Pharmaceutics & Pharmaceutical Technology, University of Uyo, Nigeria, olorunsolaeo@yahoo.com Reviewers: Prof. Hassan A.H. Al-Shamahy, Sana'a University, Yemen, shmahe@yemen.net.ye Dr. Mohaddese Mahboubi, Alzahra University, Tehran, Iran, mahboubi@barijessence.com

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease associated with unique lesional dysbiotic features. However, the role of the microbiology in the pathogenesis of HS remains in dispute. We aimed to conduct a two-sample Mendelian randomization study to investigate the relationship between skin microbiota and HS. A two-sample Mendelian randomization study was performed using the summary statistics of skin microbiota from summary GWAS data of the European descent from two cross-sectional, population-based German cohorts, KORA FF4 (n = 324) and PopGen (n = 273). The summary statistics of hidradenitis suppurativa were obtained from the FinnGen DF10 (1,070 cases and 394,105 controls). Inverse variance weighted (IVW), MR-Egger regression, weighted median, simple mode, weighted mode, and MRPRESSO were used to examine the causal association between skin microbiota and hidradenitis suppurativa. Cochran's Q statistics were used to quantify the heterogeneity of instrumental variables. Our study suggested that genus Corynebacterium in dry skin is significantly associated with HS after false discovery rate (FDR) correction (odds ratio (OR) = 1.04, 95% confidence interval (CI): 1.02-1.06, P = 0.0002, FDR adjusted P = 0.035). Additionally, we found genus Micrococcus in moist skin (OR = 1.10, 95% CI: 1.03-1.18, P = 0.0060, FDR adjusted P = 0.360), species Streptococcus salivarius in dry skin (OR = 1.03, 95% CI: 1.01-1.05, P = 0.0070, FDR adjusted P = 0.360), and species Propionibacterium granulosum (OR = 1.02, 95% CI: 1.00-1.04, P = 0.0460, FDR adjusted P = 0.970) are potentially associated with HS before FDR adjustment. No evidence of the effect in the reverse direction for HS on skin microbial features. This two-sample Mendelian randomization study found that genus Corynebacterium was causally associated with HS. Further studies are needed to clarify the protective effect of prebiotics, probiotics or microbiome transplants on HS.

Actinobacteria have frequently been reported in the Andean Puna, including strains of the genus Micrococcus. These strains demonstrate resistance to high levels of UV radiation, arsenic, and multiple antibiotics, and possess large linear plasmids. A comparative analysis of the sequences and putative functions of these plasmids was conducted. The presence of large regions with high sequence identity (exceeding 30 kb in total) in all three studied Micrococcus megaplasmids indicates a clear evolutionary link among these elements. Genes related to essential plasmid functions were primarily found within these conserved regions, while genes associated with resistance to metals and antibiotics resided in accessory regions. Moreover, the abundance of open reading frames related to transposition and recombination, along with local deviations from the average GC content, provides evidence for the mosaic nature and considerable genetic plasticity of these plasmids. This study presents evidence of a common ancestor for linear plasmids in Micrococcus and suggests that horizontal gene transfer likely occurs frequently within Andean lakes, providing the native microbial community with a beneficial gene pool to withstand extreme conditions. Additionally, the successful transfer of the linear plasmid pLMA1 by a DNase-insensitive, conjugation-type mechanism and its potential use as a genetic vector is demonstrated.

Electrochemical enrichment of a community of weak electricigens and characterisation of three halotolerant electroactive isolates: Micrococcus sp. YH-1, Gordonia sp. RH-1 and Stutzerimonas sp. CH-1

Biosurfactants are natural surfactants derived from bacteria which can degrade oil content in soil or water. Most of these biosurfactant-producing bacteria are often found in areas polluted by oil and grease, such as aerobic ponds of palm oil liquid waste. The purpose of this research was to isolate and identify biosurfactant-producing bacteria from aerobic ponds of palm oil wastewater at PT. Aek Loba Plantation. This research was conducted using descriptive and identification methods through emulsification tests, morphological characterization, gram staining, biochemical tests, and PCR (Polymerase Chain Reaction) methods for bacteria that had the highest emulsification index values. Based on the results of the emulsification test, it was found that 8 biosurfactant-producing bacterial isolates consisted of 6 bacterial genera and 1 bacterial species that had different emulsification indexes, namely 1 Citrobacter genus isolate (30%), 1 Enterobacter genus bacterial isolate (42.2%) , 2 isolates from the genus Eschericia (35.9% and 36.5%), 1 isolate from the genus Pseudomonas (32%), 1 isolate from the genus Micrococcus (37.5%), 1 isolate from the genus Bacillus, and 1 species of bacteria Klebsiella variicola (42.8%) which is a biosurfactant producing bacteria that has the highest emulsification index value.

Constipation-predominant irritable bowel syndrome (IBS-C) is a chronic functional intestinal disease that can significantly reduce patients' quality of life. This study aims to evaluate the clinical effect and mechanism of YunPi RouGan (YPRG) prescription on IBS-C patients with liver-depression and spleen-deficiency syndrome. 42 IBS-C patients receiving treatment at Jiangsu Provincial Hospital of Integrated Traditional Chinese and Western Medicine from May 2022 to March 2023 were recruited and randomly assigned to either the treatment or control group, with 21 patients in each group. The patients received either a YPRG prescription or a linalotide capsule for 4 weeks. A series of scales were utilized to evaluate the clinical symptoms, psychological aspects, and quality of life in IBS patients. Meanwhile, fresh fecal samples were collected to analyze the changes in gut microbiota by 16SrDNA sequencing. In terms of clinical treatment, both YPRG prescription and the first-line drug linaclotide have similar effects for IBS-C. However, YPRG prescription has demonstrated significant improvements in several symptoms, such as abdominal distension and belching. Furthermore, it has been shown to upregulate the diversity of gut microbiota and induce changes in the types of dominant microbiota in IBS-C patients. At the phylum level, Firmicutes and Bacteroides increased, while Proteobacteria, actinobacteria, and desulphurobacteria decreased. At the genus level, Bacteroides, Spirillum, Clostridium praxis, Roxella, Para-salmonella, Haemophilus, koala bacillus, Micrococcus rare, Spirillum, and Streptococcus increased significantly. The effect of YPRG prescription on improving the clinical symptoms of IBS-C may be attributed to its potential to regulate gut microbiota.

This study aimed to assess glucosamine production through enzymatic activity, utilizing actinomycetes sourced from shrimp shell waste (SSW) in a solid-state fermentation (SSF) process. A total of 16 actinomycetes underwent chitinase activity screening, and the strain exhibiting the highest chitinolytic index was chosen for subsequent morphological and phylogenetic analyses. High Performance Liquid Chromatography (HPLC) was employed to analyze glucosamine produced from the bioconversion of SSW via SSF. Optimal conditions for glucosamine production were determined by varying time, pH, and temperature. Isolate 18D36-A2 showed the highest chitinolytic index of 1.02 in the 32-mm clean zone. Phylogenetic analysis revealed 97% similarity to the genus Micrococcus, identifying it as a novel Micrococcus unila strain 18D36-A2 and deposited in GenBank. This isolate effectively converted shrimp shells. The findings showcase the bioconversion of SSW to glucosamine through SSF using the Micrococcus unila 18D36-A2. Furthermore, this study establishes a foundation for future research on environmentally friendly and sustainable designs for glucosamine production.

Sponge Haliclona sp. is a type of sponge living in marine waters and is found in many areas of coral reef ecosystems. This study aimed to determine the potential for sponge Haliclona sp. obtained from Tanjung Tiram waters, Konawe, as a source of bioactive compounds of MDR (Multidrug-Resistant) antibacterial. The isolation method of Haliclona sp. symbiont was carried out by pouring and purification of Haliclona sp. symbiont using the scratch method. The purification results obtained 12 isolates of symbiont bacteria that were successfully isolated. Then the bacterial isolate was tested for its antibacterial ability against MRSA and ESBL Escherichia coli bacteria qualitatively using the agar diffusion method. Bacteria that have strong inhibitory activity are identified by morphological and biochemical tests. The results of the qualitative screening test produced four bacterial isolates that have inhibitory activity against MRSA (Methicilin Resistant Staphylococcus aureus) pathogenic bacteria with the isolate codes H3 and H8 belonging to the strong category while H4 and H10 belonging to the medium categoy. Additionally, two bacterial isolates that have inhibitory activity against ESBL Escherichia coli pathogenic bacteria with the isolate codes H3 and H8 belonging to the strong category. Based on morphological observations and biochemical tests, the H3 bacterial isolate was identified as the genus Corynebacterium spp. and the H8 bacterial isolate was identified as the genus Micrococcus spp. In conclusion, Haliclona sp. sponge exhibits promising potential as a source of microorganism producing antibacterial compounds, particulary againts MDR (Multidrug-Resistant) strains.

This research focuses on the isolation and thorough characterization of a distinctive pigment-producing bacterial strain, ACFM05, obtained from Daucus carota subsp. Sativus (Carrots). The pigment was systematically examined for morphological, microscopic, biochemical, and molecular features, utilizing 16S rRNA sequencing. The strain was identified as a novel species within the Micrococcus genus, specifically classified as Micrococcus yunnanensis. The optimization of pigment extraction parameters revealed a pH of 8 at 40 °C as the ideal conditions for maximum yield. UV studies indicated that the pigment, extracted with methanol as the solvent, exhibited a notable absorption peak at 445 nm, closely resembling the absorption peak of carotenoids. The growth biomass of the bacteria was found to be influenced by the antioxidant activity, reducing power assay, and total phenolic content. The pigment extracts were further evaluated for their antifungal, antibiotic sensitivity, and antibacterial activities against Pseudomonas, Staphylococcus aureus, and Escherichia coli. Results indicated significant potential for the pigment as an antimicrobial agent. To elucidate the molecular and structural characteristics of the pigment, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric-differential thermal analysis (TG-DTA), and scanning electron microscopy (SEM) analyses were employed. The findings from these analyses collectively confirmed the presence of carotenoids in the bacterial pigment. Furthermore, XRD studies revealed the crystalline nature of the pigment. In conclusion, the unique crystalline pigment isolated from Micrococcus yunnanensis ACFM05 demonstrates promising potential as a natural colorant for food applications. This study contributes valuable insights into the microbial production of pigments with multifaceted applications in the food industry.

A novel actinobacterial strain, designated as JXJ CY 30 T, was isolated from the phycosphere of Microcystis aeruginosa FACHB-905 (Maf) collected from Lake Dianchi, China. The strain was a Gram-stain-positive, aerobic and coccus-shaped actinobacterium. It had alanine, glutamic acid, aspartic acid, and lysine in the peptidoglycan, and mannose, ribose and arabinose in its cell wall sugars, anteiso-C15:0 and iso-C15:0 as the main cellular fatty acids, MK-7 and MK-8 as the major respiratory quinones, and phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, glycolipid, and an unidentified phospholipid as the polar lipids. The DNA G + C content was 73.08%. Its 16 S rRNA gene sequence shared 99.14%, and 98.75% similarities with Micrococcus flavus DSM 19079 T and M. porci KD337-16T, respectively, and ≤98.41% similarities with other type strains of the genus Micrococcus. It formed independent clade with M. flavus DSM 19079 T on the phylogenetic trees. The digital DNA-DNA hybridization and average nucleotide identity values between strain JXJ CY 30 T and M. flavus DSM 19079 T and M. porci KD337-16T were 48.0% and 92.1%, 25.5% and 83.2%, respectively. These data above indicated that strain JXJ CY 30 T represented a new species of the genus Micrococcus, and the species epithet is proposed as Micrococcus lacusdianchii sp. nov. (type strain JXJ CY 30 T = KCTC 49378 T = CGMCC 1.17508 T). Strain JXJ CY 30 T can potentially provide Maf with various nutrients such as available phosphorus and nitrogen, plant hormones, various vitamins and carotenoids for growth, while it was inhibited by metabolites from its symbiotic algae Maf.

The use of enzymes in Indonesia is increasing every year, so action is needed to harmonize the production and needs of enzymes in Indonesia. Enzymes can be produced from various sources such as plants, animals and microorganisms. The advantage of utilizing microorganisms in enzyme production is that they can be produced in large quantities with a shorter time and can be produced continuously. One of the sources of bacterial screening to produce enzymes is figs. This study aims to look at the extracellular enzyme activity of fig endophytic bacteria and identify endophytic bacteria capable of producing extracellular enzymes such as proteases, amylase, cellulase and lipase. Isolation and purification of bacteria using NA media for 24 hours. Test of extracellular enzyme activity using NA media enriched with amylum, tween 80, skim milk, CMC. Biochemical tests are performed to identify endophytic bacteria of figs producing extracellular enzymes. The results of the study were 21 isolates of fig endophytic bacteria, as many as 14 isolates were able to produce extracellular enzymes. The identification results of fig endophytic bacteria producing extracellular enzymes obtained 8 isolates suspected to be from the genus Bacillus, 3 isolates suspected to be from the genus Micrococcus, 1 isolate suspected to be from the genus Cellulomonas, 2 isolates suspected to be from the genus Acetobacter

Lateritic soil is the reddish to brown-colored soil composed mainly of iron or aluminium oxides, hydroxides, or oxyhydroxides. Information on bacteria that inhabit this soil type, their ecological role, and metabolic potential are scarce. We have isolated and partially characterized a bacterial strain BirBP01 from a lead, calcium, and magnesium-rich, oligotrophic subsurface lateritic soil-sample collected from 12-feet deep horizon of a laterite mining pit in Birbhum district, India. The isolate is a biofilm-forming, Gram-positive bacterium having a sarcinae arrangement, mesophilic, slightly alkaliphilic, able to produce amylase, and resistant against multiple heavy-metals. BirBP01 has the ability to bioremediate 51% of Pb, 30% of Zn, and 22% of Cu through biosorption, possibly into the biofilm matrix. The bioremediating ability of the bacterium alleviated the inhibitory effect of heavy-metals on the germination of chickpea (Cicer arietinum L.) seeds. 16S rRNA gene-based phylogenetic analysis revealed that BirBP01 is a member of the genus Micrococcus. It showed more than 99% identity of the 16S rRNA gene sequence, and clustered within the same branch of the phylogenetic tree, with strains of M. yunnanensis, M. endophyticus, and M. luteus. The ability to produce amylase, and bioremediate heavy-metals signify that Micrococcus sp. BirBP01 could bepotentially a good candidate for industrial applications, and to clean up heavy-metal contaminated sites.

Ultraviolet radiation (UVR) is a known environmental key factor for premature skin ageing. Only few scientific evidence is available to support the effects of UVR on the skin microbiome. This in vivo pilot study aimed to evaluate the impact on the skin microbiome upon erythemal UV exposure and the protection of UV-exposed skin microbiome by UV filters. Ten female volunteers were treated with an sun protection factor (SPF) 20 sunscreen and placebo formulation (without UV filters) on their upper middle backs and irradiated with an erythemal dose (2 MED) by a solar simulator. Skin swabbing samples from four zones (i.e., unexposed, exposed, sunscreen- and placebo-treated on exposed skin) were collected for the microbiome analysis before and 2 h after UV exposure, respectively, and processed via shallow 16S rRNA Amplicon and Shotgun metagenomic sequencing. An in vitro UV method was developed to confirm the protection of isolated bacterial strains by single UV filters and combinations. Alpha diversity was impacted by significant inter-individual differences and by treatment rather than by irradiation. Cutibacterium acnes was found to be the most abundant and a confounding factor for diversity. On a species level, Lactobacillus crispatus was negatively associated with UVR and placebo treatment, whereas there was a positive association with sunscreen treatment. The sunscreen treatment also favoured an interaction network with central Micrococcus genus. The in vitro results showed that both single UV filters and combinations had specific effects on the survival rates of L. crispatus, C. acnes, and Staphylococcus epidermidis. We identified potential microorganisms and bacterial interactions that were associated with an SPF 20 sunscreen treatment. The specific protection of L. crispatus as a key player in the UV-exposed skin microbiome and reduction of C. acnes population by UV filters might lead to new cosmetic concepts for photoprotection.

This study focused on the investigation of Exopolysaccharide (EPS) producing bacteria from Sundarbans mangrove forest (SMF) soil, Bangladesh. The heterotrophic bacterial loads in the soil samples varied from 0.44×107 to 4.2×107 cfu/g indicating high bacterial load even under hostile environment. Fifteen EPS producing bacterial isolates were identified provisionally where thirteen isolates belonged to the genus Bacillus including B. badius (n=1, 6.67%), B. subtilis (n=3, 20.0%), B. pumilus (n=3, 20.0%), B. brevis (n=2, 13.33%), B. stearothermophilus (n=2, 13.33%), B. sphaericus (n=1, 6.67%) and B. alcalophilus (n=1, 6.67%). The remaining two isolates were recognized as the genus Micrococcus sp. (n=2, 13.33%). The genus Bacillus was predominant representing 86.67% abundance frequency. The LB medium was proven to be the most suitable medium for the growth of EPS producing bacterial isolates. 16S rDNA sequence analysis was conducted for three EPS producing bacterial isolates and they were identified as Bacillus subtilis, B. strearothermophilus and Micrococcus sp. The antibiogram profile of this study revealed streptomycin as the most effective antibiotic to control the growth of bacteria. The presence of antibiotic resistance bacteria in SMF soil is alarming for human health associated with this marine ecosystem. The multidrug resistance bacteria may come to the soil of SMF through the untreated discharged wastewaters and agricultural runoff from adjacent areas. Dhaka Univ. J. Biol. Sci. 32(2): 243-255, 2023 (July)

To maintain asepsis in production environments, contamination must be constantly controlled. To this end, microbiological monitoring is constantly used with the objective of evaluating the incidence of microorganisms prevalent in the sampling of air, surface, and people, in the area of an environment considered aseptic, isolated, and identified using the rapid and automated phenotypic microbiological methodology, highlighting the MALDI-TOF mass spectrometry analysis technique (MS), being identified at the level of genus and/or species. For that purpose, microbiological control of environmental monitoring of environments considered aseptic in a pharmaceutical industry was conducted for 12months. The isolated microorganisms were identified using the mass spectrometry identification method (MALDI-TOF). In area classification A, the most prevalent microorganisms were bacteria in the sampling person. The microbial population was composed of bacteria of the genus Micrococcus sp. and Staphylococcus sp. Based on the results, it is possible to observe that in an environment where the process requires human operations, possible microbial contamination is inevitable and requires the identification of microorganisms at least at the level of species and/or genus. The microorganisms identified and found in the sampling of the aseptic environment must be evaluated with frequency to ensure that the productive environment guarantees the quality of the product produced.

The complex (quantitative and qualitative) characteristics of prokaryotic communities of solid atmospheric fallouts (dust aerosol) and soils in the territory of Moscow in areas with different intensity of anthropogenic load have been done. The total number of bacteria in the studied samples of solid atmospheric fallouts (SAF) was lower than the number of bacteria in soil samples; actinomycete mycelium was not found in the dust samples, although it was found in soil samples. The number of culturable saprotrophic bacteria in dust samples was an order of magnitude lower than in Urbic Technosols taken from the same plots. Representatives of the genus Micrococcus dominated among cultivated bacteria in the dust aerosols, while representatives of the phylum Proteobacteria dominated in soils. Representatives of the Enterobacteriaceae family were found in the dust samples, among which there are species that are potential human pathogens. The maximum biodiversity of bacteria of the Enterobacteriaceae family was recorded in the dust samples taken in areas with increased anthropogenic and transport load. The sanitary-indicative bacterium Escherichia coli was found in all samples of the dust and Urbic Technosols, its content varied (from 10 to 100 CFU/g), according to the degree of epidemic danger it characterizes dust and soils as moderately dangerous. Ecological indices calculated for prokaryotic communities in situ (barcoding of the 16S rRNA gene) indicate a lower taxonomic diversity of SAF prokaryotic communities compared to communities of closely spaced Urbic Technosols.

The aim of this study was to assess bacterial aerosols in a herbal processing plant in Poland. Bioaerosol measurements of indoor and outdoor air of the herbal processing plant were performed in four measurement rounds, in a seasonal cycle—in spring, summer, autumn, and winter—using a six-stage Andersen’s cascade air sampler. At each measuring point, during the bioaerosol sampling, the values of relative humidity and air temperature were simultaneously measured using the Kestrel 4000 device, and the concentration of particulate matter (fractions 1.0 μm, 2.5 μm, 4.0 µm, and 10.0 µm) using a DustTrak II dust analyzer. The results showed that the production process affects the bacterial aerosol concentrations in the tested plant. There were statistically significant differences in the concentrations of bacterial aerosol between indoor and outdoor air, and between production rooms, taking into account the seasons of the year. The concentrations of bacterial aerosol in the production rooms did not exceed 7.6 ×·103 cfu·m−3 and were lower than the permissible concentration values proposed for production rooms contaminated with organic dust. The calculations showed a significant correlation between the concentration of bacterial aerosol and air temperature. Qualitative analysis of microorganisms isolated from the air of production rooms showed the dominance of Gram-positive cocci of the genus Micrococcus and spore-forming rods of the Bacillus genus. The study confirmed that herbal processing plants may be related to exposure to microbiological agents.

Even though ozone has shown its potential for air disinfection in hospital environment, its more frequent use has earned attention only with the COVID-19 pandemic due to its proven antimicrobial effect and low cost of production. The aim of this study was to determine its antimicrobial efficiency against the most common bacterial species in a real-life setting, that is, in the air of one postoperative room of the General Hospital Dr Ivo Pedišić (Sisak, Croatia). Air was sampled for aiborne bacteria before and after treatment with the ozone concentration of 15.71 mg/m3 for one hour. The most dominant Gram-positive bacteria of the genera Micrococcus, Staphylococcus, and Bacillus were reduced by 33 %, 58 %, and 61 %, respectively. The genus Micrococcus proved to be the most resistant. Considering our findings, we recommend longer air treatment with higher ozone concentrations in combination with mechanical cleaning and frequent ventilation.

BackgroundCharacteristics of the blood microbiota among adult patients with community-acquired sepsis are poorly understood. Our aim was to analyze the composition of blood microbiota in adult patients with community-acquired sepsis, and correlate changes with non-septic control patients.MethodsA prospective observational study was carried out by including adult patients hospitalized for community-acquired sepsis at our center between January and November 2019, by random selection from a pool of eligible patients. Study inclusion was done on the day of sepsis diagnosis. Community acquisition was ascertained by a priori exclusion criteria; sepsis was defined according to the SEPSIS-3 definitions. Each included patient was matched with non-septic control patients by age and gender in a 1:1 fashion enrolled from the general population. Conventional culturing with BacT/ALERT system and 16S rRNA microbiota analysis were performed from blood samples taken in a same time from a patient. Abundance data was analyzed by the CosmosID HUB Microbiome software.ResultsAltogether, 13 hospitalized patients were included, 6/13 (46.2%) with sepsis and 7/13 (53.8%) with septic shock at diagnosis. The most prevalent etiopathogen isolated from blood cultures was Escherichia coli, patients mostly had intraabdominal septic source. At day 28, all-cause mortality was 15.4% (2/13). Compared to non-septic control patients, a relative scarcity of Faecalibacterium, Blautia, Coprococcus and Roseburia genera, with an abundance of Enhydrobacter, Pseudomonas and Micrococcus genera was observed among septic patients. Relative differences between septic vs. non-septic patients were more obvious at the phylum level, mainly driven by Firmicutes (25.7% vs. 63.1%; p<0.01) and Proteobacteria (36.9% vs. 16.6%; p<0.01). The alpha diversity, quantified by the Chao1 index showed statistically significant difference between septic vs. non-septic patients (126 ± 51 vs. 66 ± 26; p<0.01). The Bray-Curtis beta diversity, reported by principal coordinate analysis of total hit frequencies, revealed 2 potentially separate clusters among septic vs. non-septic patients.ConclusionIn adult patients with community-acquired sepsis, specific changes in the composition and abundance of blood microbiota could be detected by 16S rRNA metagenome sequencing, compared to non-septic control patients. Traditional blood culture results only partially correlate with microbiota test results.